Emergency crews have cordoned off an area near a Tesco store amid reports of an “explosion and underground rumbling.”
Firefighters were called to the Porthmadog site earlier this morning.
Power supplies to some nearby properties has been affected and utility companies are making their way to the scene.
Witnesses report hearing a loud bang with some saying they have seen an “explosion” and smoke coming from the ground.
We will bring you all the latest updates as we get them.
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